MacRumors Forum poster aibnr noticed earlier today that the iOS 7 Beta 4 download appeared to be posted on Apple's developer servers early this morning, ahead of an expected release today. If released today, Beta 4, with a rumored build number of 11a4435d, would come three weeks after Beta 3 was released at the beginning of July.

Clicking the purported download link, available here, returns a 'Your session has expired' error page. Other URLs with similar build numbers, on the other hand, return an 'Access Denied' error message.

Additionally, one source has informed us that the company plans to release just two more betas for developers before the gold master (GM) version is released in early September.

9to5Macsomewhat corroborates this, claiming that Apple is nearing "zero-priority-1 bug status", meaning there are no critical bugs left in the OS and the company is getting close to releasing a "GM1" candidate internally. Apple typically releases several internal GM candidates before releasing a final GM seed to developers for testing.

On my iPhone 5 b3 works flawlessly other than a few rogue apps *cough* Skype, which I suspect is possibly more APIs than actual bugs, but on my 3rd gen iPad it's pretty darn buggy, so I hope there's a few more betas. Unless it's all fixed in b4, in which case RELEASE RELEASE RELEASE!

Most the actual instability and battery drain went away between 2->3. I'm hoping that 3->4 resolves some of the odd visual issues like the lock screen displaying with content stuck in it from time to time. You'd be amazed how much can get done in a few weeks of software development though. I'm sure it's gotten a lot better. If they're shooting for 2 more betas before release I'm sure this will get them in line with previous major releases in terms of stability. There's always going to be issues that aren't discovered until millions of users are running the release. That's just the nature of developing software.